Temporal and Frequency Characteristics of Turkish Vowels in Laryngectomized Speakers: Preliminary Study

Abstract

Objective: In the alaryngeal speech acoustics, formant frequencies and durations of vowels are two most fundamental parameters .However, it is not clear if the vocal tract transmission properties and temporal characteristics of vowels vary related to alaryngeal speech type. The main purpose of this study is to compare the formant frequency and duration characteristics of Turkish vowels between the esophageal, tracheoesophageal, and laryngeal speakers. Methods: Formant frequency and duration values of 8 Turkish vowels have been defined and these values were compared between the esophageal, tracheoesophageal, laryngeal speakers. Detection of a formant was based on Linear Predictive Coding and Fast Fourier Transform. Results: Except the vowels /y/ and /i/; F1 and F2 frequency values of alaryngeal speakers were higher than laryngeal speakers both in the initial and final position. Alaryngeal groups' vowel space areas have been diminished. The vowels in the final position had longer durations comparing to their initial position in all groups. Conclusion: The results of this study generally supported the shorter vocal tract and frontedhigher tongue position in Turkish alaryngeal speakers. The minor differences between other studies are thought to arise from the differences in consonantal context and possible coarticulatory effects. Acoustic findings obtained in the present study, indicated that transesophageal speech is more similar to laryngeal speech as compared to esophageal speech. However, further studies including higher number of participants are needed to verify the findings of this study.

High vowel weakening in Turkish

“…The only experimental works entirely devoted to Turkish HVW are Jannedy (1994Jannedy ( , 1995 and Ay & Bekâr Uzun (2015), and they are mainly focused on devoicing (the latter only discussing /ɯ/). To our knowledge, HVS has never been investigated comprehensively; a few works (e.g., Şayli 2002, Şayli & Arslan 2003, Arısoy et al 2004, Aydınlı 2018, Ergenç & Bekâr Uzun 2020: 107-10, Lorenzen 2021) report measurements of Turkish vowel durations, and do consistently find that high vowels are shorter than non-high ones (see for example Table 1 below, which reproduces measurements from Arısoy et al 2004) The aim of this paper is thus twofold: first, we want to expand the empirical data on Turkish HVS. Second, we want to understand whether it is purely phonetic or if it is controlled by a (semi)categorical phonological process.…”